Field of the Invention
This invention relates to hybrid electrical and optical cable assemblies. More particularly, the invention relates to a shielded furcation assembly for electrical conductors of a hybrid electro-optical cable.
Description of Related Art
The wireless communications industry is changing from traditional signal delivery from ground based transceivers delivering/receiving the RF signal to/from the antenna atop the radio tower via bulky/heavy/high material cost metal RF coaxial cable to optical signal delivery to a tower top mounted transceiver known as a remote radio unit (RRU) or remote radio head (RRH) with implementation of fiber to the antenna (FTTA) cabling.
FTTA cabling may be simplified where power and/or control signal conductors are provided with optical signal conductors in a single hybrid electro-optical cable 3. An FTTA cable, for example as shown in FIG. 1, may include a metallic shield 2 surrounding multiple electrical conductors 5 and single or multiple optical conductor (fibers) 7 in a subunit. A fiber subunit may include multiple optical fibers (such as 250 um or 900 um). Optical conductors may be fragile, requiring great care to properly terminate.
Prior hyrbrid cable RRU/RRH terminations have employed an over voltage protection and/or distribution box for terminating each of the electrical and optical conductors as individual jumpers. These additional enclosures require field termination of the several conductors atop the radio tower, increasing installation time and labor requirements. Further, each break in the conductors provides another opportunity for signal degradation and/or environmental fouling. Standardized electrical interconnection interfaces of the RRU/RRH equipment may include shielded connector interfaces to isolate the power conductors from lighting strike and/or the RRU/RRH equipment from electro-magnetic interference (EMI) that the electrical conductors may generate.
Factory terminated hybrid cable assemblies are known. However, these assemblies may apply splices to the conductors, require a relatively large in-line break-out/splice enclosure and/or utilize environmental seals which fail to positively interlock the jumpers therewith, which may increase the potential for cable and/or individual conductor damage to occur.
Furcation tubes may be applied to fibers and or fiber bundles stripped back from the cable end to protect the optical fibers from damage between the cable and the optical fiber termination. Optical fiber furcation tubes may consist of an inner polymer tube surrounded by a para-aramid synthetic fiber sheath, or a para-aramid synthetic fiber sheath alone.
Therefore, an object of the invention is to provide an electro-optical cable furcation assembly solution that overcomes deficiencies in the prior art.